Biochemical and neuroendocrine approaches to a malignant syndrome of neuroleptics

A 20 year old patient who has been hospitalized for depressive schizoidia was treated with nomifensine (75 mg/d) plus pimozide (4 mg/d). Four days later, he showed a typical neuroleptic malignant syndrome (syndrome malin de Delay et Deniker). The biological explorations show that inflammatory blood tests are increased, hepatic tests are disturbed and the pituitary tests suggest a hypothalamic disturbance of the balance between NE and DA (reduced STH, FSH and LH) with a relative NE predominance, but also an increase of DA (increased HVA in CSF). A pathogenic interaction between nomifensine, an antidepressant inhibiting the reuptake of NE and DA, and pimozide, a neuroleptic blocking dopaminergic postsynaptic receptors is considered.